Last year the word Zapad was on everyone's lips, just as the Kremlin surely wanted with its drills practicing an invasion of the Baltic states from a stone's throw away. But Vostok 2018, despite being billed by Moscow as its largest exercises since the height of the Cold War, isn't setting NATO's pulse racing — nor prompting reinforcements to its eastern flank.

"Monitoring" is the term used both by alliance spokespeople publicly and NATO insiders privately to describe the posture being taken during the week-long exercises with China. That's due in large part to the fact that the Vostok training ground is way over in eastern Siberia, so there's not the same fear as there was with Zapad in Belarus that Russia will simply leave some forces in a place too close for comfort.

Read more: Things to know about international military exercises

Elisabeth Braw, a deterrence expert with the London-based Royal United Services Institute for Defense and Security Studies (RUSI), said it's understandable that NATO isn't particularly concerned, but she believes China's new chumminess with the Kremlin is nonetheless notable. "It sends a signal that the two of them are teaming up and we, the West, don't have a strong ally in either of them," she told DW. "I think we had the expectation that China would side with us — maybe not on every issue but us on some issues."  Braw says that longstanding presumption perhaps can't be taken for granted anymore.

"Showing military strength has several purposes" for Russian President Vladimir Putin, explained Roland Freudenstein of the Martens Center in Brussels. "It's certainly showing military strength also to his own people and a distraction from all the domestic crises, starting with the pension reform, which is very unpopular." But, Freudenstein added, "It's part of the game that Putin is playing with the West ... to scare NATO countries, especially the smaller ones."

Airborne assurance

But those countries are getting ever more reassurance from above, from NATO's eyes in the skies, the air-policing program that keeps fighter jets on alert 24/7 at nearly three dozen air bases throughout NATO territory. Initiated in the Baltics in 2004 and continually expanded all the way to Montenegro, when it joined NATO last year, the program overseen out of Ramstein Air Base in Germany has ensured there's been no major violation of NATO airspace.

That's not for lack of trying, as statistics show the alliance scrambled jets 250 times last year to respond to Russian aircraft coming close to NATO airspace. That's just a third of the incidents in 2016, when there was a major spike up to 780 occurrences.

More menaces than Moscow

Beyond this Russian "buzzing," which has almost become routine, these forces are also on standby in case of civilian aircraft losing communication with air-traffic controllers for any reason, ranging from technical failure to hijacking.

Read more: US General Ben Hodges: 'Russia only respects strength'

"Our mission is to protect the borders. Anything that approaches a border and is not authorized to cross that border is an incident for us," explained Spanish Air Force Lieutenant General Ruben Garcia Servert, commander of NATO's southern Combined Air Operations Center in Torrejon, Spain.

"It's true that today many cases are Russians, but we can expect anything," he told DW. "We are there, we have solidarity, we have integrated our system to make sure that our borders are protected from anything."

DW was invited to join a training flight this week, which officials say was only coincidentally being held during Vostok. Nevertheless, the demonstration of NATO's powerful air defense is surely not an unwelcome image to project. In an unprecedented exhibition flight, a Belgian Air Force plane posed as a "renegade" intruder, flying from Brussels to Spain.

Read more: NATO in Baltics learns from Ukraine's mistakes

Shortly after take-off in the simulated COMLOSS incident — where there's no information coming from the plane to air traffic controllers on the ground — two German Air Force Eurofighters appeared tight on the wings of the Belgian Airbus, switching from side to side, penning it in. As ground borders were crossed, fighter jets of almost a dozen nationalities zoomed in to escort the flight, JAS-39 Gripens flown by the Czechs and Hungarians, MiG-21s and -29s from Croatia and Slovakia, the British Eurofighter Typhoon.

In a real interception those pilots would be using internationally-recognized hand signals to try to communicate with the Belgian pilot to figure out why he's not in touch with ground control; whether he's in trouble — or making trouble. In this case, even the experienced Belgian pilot was so enthralled with the private air show that he was taking photos from the cockpit each time a new breed swooped alongside.

Taking stock since 9/11

Servert revealed that his biggest concern currently is not the Russians: It's the unpredictable threats emanating from the Mediterranean region where non-state actors, meaning potentially terrorists, can find safe haven in unstable countries and then take aim at NATO allies.

"For us it's extremely dangerous," Servert said, "because it's not, in today's world, only states who can launch an aircraft that will make harm in our area. This area of uncertainty that is developing in the south ... we keep an eye on that area."

At the same time he maintains a high degree of confidence in the range of tactics available to NATO pilots. Servert emphasized that, regarding potential misuse of civilian aircraft, the first line of defense is on the ground, as dangerous people should never make it onto a plane. However, Servert explained, the 9/11 attacks in the US were such a turning point in understanding these threats that if something like those hijackings were attempted again in the airspace NATO monitors, he believes it would be possible to thwart them.